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Euclid 'dark universe' telescope gets de-iced from a million miles away
Mar 19, 2024
Just like drivers scrape ice from car windshields during the winter, scientists with the European Space Agency's (ESA) Euclid observatory are trying to "de-ice" the telescope â from a million miles away.
Ice layers, about as wide as a single DNA strand, have accumulated on Euclid's mirrors. Although small, the ice appears to have caused "a small but progressive decrease" in the amount of starlight the telescope is capturing, the agency said in a statement on March 19 (Tuesday). The telescope continues its science observations for now while scientists begin heating low-risk optical parts of the spacecraft to begin a de-icing process. These low-risk areas correspond to sections on the telescope where released water is unlikely to impair other instruments, the agency said.
"De-icing should restore and preserve Euclid's ability to collect light from these ancient galaxies, but it's the first time we're doing this procedure," said Reiko Nakajima, a Euclid scientist at the University of Bonn in Germany. "We have very good guesses about which surface the ice is sticking to, but we won't be sure until we do it."
The problem is not entirely uncommon for space telescopes. Scientists know it is close to impossible to prevent miniscule amounts of water in the air from making its way into spacecraft during assembly, so "it was always expected that water could gradually build up and contaminate Euclid's vision," ESA said in Tuesday's statement.
Shortly after Euclid's launch in July of last year, scientists had warmed the telescope using onboard heaters to evaporate most of the water molecules that would have entered the spacecraft prior to liftoff. But it appears "a considerable fraction" survived, perhaps by being absorbed into the telescope's multiple layers of insulation, which have gotten loose since reaching the vacuum of space. In space's frigid environment, these molecules tend to stick to the first surface they land on, one of which appears to be the telescope's mirrors.
The issue first came to light when the mission team noticed a gradual decrease in starlight measured with one of Euclid's two science instruments, called the visible instrument (VIS). To help catalog 1.5 billion galaxies and their stellar populations, VIS collects visible light from stars similar to how a smartphone camera operates, only with 100 times as many pixels. Its resolution is thus equivalent to a 4K screen.
"Some stars in the universe vary in their luminosity, but the majority are stable for many millions of years," Mischa Schirmer, a Euclid scientist who is leading the de-icing campaign, said in the statement. "So, when our instruments detected a faint, gradual decline in photons coming in, we knew it wasn't them â it was us."
The easiest solution would be to heat the entire spacecraft, but doing so would also warm up the telescope's mechanical structure, whose components would expand but not necessarily return to their original states even after a week, the mission scientists say. That would limit Euclid's vision and, in turn, impact the quality of data it gathers. The telescope is influenced by even the tiniest of temperature changes. So, Schirmer and her colleagues are planning to first heat up low-risk, optical parts of Euclid, starting with two mirrors that can be warmed independently of one another and then monitor how the change influences the amount of light VIS gathers.
This icy dilemma marks the second problem with the spacecraft in one year. Last September, a sensor meant to find stars for navigation purposes incorrectly tagged cosmic rays as stars, meaning the telescope couldnât resolve the star patterns it relied on to point itself at specific areas in the sky. The issue was fixed a month later.
As for the latest issue, scientists expect tiny amounts of water to continue being released over Euclid's six-year life in orbit. So if they are successful with the de-icing campaign this time, the same procedure could keep Euclid's systems ice-free for the rest of its mission.
https://www.space.com/euclid-dark-universe-telescope-de-icing-process-mirrors-esa
https://www.thesun.co.uk/news/26770964/ufos-unidentified-subs-real-threat-ex-us-admiral-warning/
UFOs are one thing â but unidentified SUBS are the real threatâŚâUSOsâ lurk in the unexplored depths, ex-US admiral warns
Updated: 1:54, 19 Mar 2024
Rear Admiral and oceanographer Tim Gallaudet said Unidentified Submersible Objects - or USOs - need urgent and focused research as they could be lurking in the unexplored depths of our oceans.
In his latest report, Rear Admiral Gallaudet explained how this is an under-researched phenomenon, and not aliens hiding under our oceans.
The ex-US military described USOs as "large lighted craft", often seen under the sea surface on their own "or as part of a group in formation."
In a chilling warning, Gallaudet said these unknown bodies can sometimes travel in the deep ocean waters without ever emerging.
And because most research focuses on what is going on up in the sky, it means that major powers could be making moves underwater without barely anyone knowing.
Gallaudet said: "We have less research on transmedium UAP and USOs than is ideal.
"These underwater anomalies jeopardise US maritime security, which is already weakened by our relative ignorance about the global ocean.
"Their presence in the oceans at the same time presents an unprecedented opportunity for maritime science.
"To meet the security and scientific challenges, transmedium UAP
and USOs should be elevated to national ocean research priorities."
Rear Admiral Gallaudet has therefore urged the US government and the international community to take action and prioritise the research on UAPs and USOs.
This would be to mainly meet the maritime security challenge posed by what he described as "hard" threats.
Such "proliferating and overwhelming" threats are said to be mainly stemming from Putin's war in Ukraine, the Israel-Hamas war, as well as Iran's proxy conflicts in the Red Sea, North Korea's ever-increasing nuclear arsenal, and China's dangerous moves towards Taiwan.
"'Hard' security threats appear to be proliferating, and an overwhelming majority affect the maritime domain," Gallaudet said.
"Russia is continuing its brutal conflict in Ukraine, where the Black Sea is the scene of a hot naval war. Another war is raging between Israel and the terrorist group Hamas, which prompted the deployment of a US Navy aircraft carrier strike group to the region.
"Those same US Navy assets are intercepting strike after strike by Iranâs proxies on international shipping in the Red Sea.
"Meanwhile in the Indo-Pacific, North Korea is ramping up its nuclear saber-rattling at the West, and China is persisting in its military aircraft incursions in Taiwanâs Air Defense Identification Zone."
The ex-US Navy also mentioned the abundance of "soft" challenges.
"China is the dominant actor in this arena," he said.
"Whether by economic coercion through state-owned enterprises or environmental degradation of all kinds, such as marine pollution, coral reef destruction, illegal fishing, and unchecked greenhouse gas emissions.
"One threat that may be even greater than all these is largely unseen: the worldwide network of undersea cables that provide the backbone of global communication and information transfer.
"This vast complex of seabed infrastructure underpins global commerce, military readiness and logistics, and the internet itself.
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"To be sure, this threat and the others outlined above paint a problematic picture for maritime security."
Gallaudet, who previously urged the American government to take action in international UFO research, labelled the under-sampling of the world's oceans as an "unsettling" and "critical concern" for maritime security.
That is because despite the ocean covering 71 per cent of the Earth's surface, less than 25 per cent of the seabed has been mapped, and a mere five per cent of the ocean volume has been explored.
It means that more is known about the surfaces of Mars and the moon than that of our own planetâs seafloor.
Gallaudet went on to claim that the US government is allegedly "not sharing all it knows" on UAPs and USOs - making it difficult to tackle security threats across the planet's oceans.
He said: "The geophysical undersampling of the worldâs ocean is a critical concern for maritime security, as obtaining and maintaining knowledge of threats on and under the sea remains a perpetually unfinished task.
"The fact that unidentified objects with unexplainable characteristics are entering US water space and the DOD is not raising a giant red flag is a sign that the government is not sharing all it knows about all-domain anomalous phenomena.
"An effective and complete approach to maritime security must seek to uncover the âunknown unknownsâ associated with transmedium UAP and USOs."
The Rear Admiral argued that further knowledge on these unidentified objects roaming the world's waters could transform "virtually any economic sector - not to mention defence".
These include air and maritime transportation, energy generation, agriculture, communications, computing, manufacturing, and space travel.
"Further study of UAP may lead to discoveries that make those of the scientific revolution in the seventeenth and eighteenth centuries look like baby steps," he said.
Gallaudet also mentioned how pilots, "credible observers" and ultra-modern military technology have recorded objects "accelerating at rates and crossing the airâsea interface in ways not possible for anything made by humans."
It comes after odd sightings were also reported by locals and UFO enthusiasts.
In June 2022, dramatic footage appeared to show a series of bright lights hovering over San Diego.
The mysterious video shared online on Monday fueled locals to wildly speculate if UFOs were flying over the Pacific Ocean.
Other bizarre footage of a large "cube" hovering above the ocean sparked a number of fresh UFO theories.
Theorist Scott C Waring claimed he saw an odd shaped UFO while watching livestreams from the International Space Station (ISS).
Posting on YouTube, the UFO hunter, who is best known for making the eccentric claim he saw a 10,000 year old alien face carved on Mars, believes the mysterious "craft" was getting ready to leave the ocean for space.
The footage from ISS taken in October 2021 showed a cloud-like substance staying motionless right above the ocean.
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